The invention relates to the field of cake production, and in particular, to production of cakes of ice confectionery containing integrated decorative layers of crisp material.
European Patent Application Publication No. 44 689 discloses a method and a device for producing cakes of ice confectionery using a rotary joint enabling the continuous extrusion of twisted multi-coloured strands of ice-cream. A device of this type does not enable the simultaneous extrusion of ice cream at a negative temperature and of a composition which becomes hard in contact with the ice cream but which has to be distributed in a liquid form, therefore at a temperature above ambient temperature, as the nozzle would be rapidly blocked.
European Patent Application Publication No. 328 170 discloses a device for decorating cakes of ice confectionery which also uses a rotary joint moved by a programmable automatic device. In an embodiment, the device makes it possible to decorate round cakes with scallops, by acting on the relative rates of flow of ice cream and the speed of rotation of the rotary joint of the distributor. In this case as well, provision is not made for the simultaneous extrusion of a plurality of materials whose behaviour on fusion is very different.
European Patent Application Publication No. 434 857 discloses a system for the simultaneous distribution of ice cream and chocolate which comprises the movement of two streams of ice cream and liquid chocolate, the ice cream taking up the chocolate outside the extrusion nozzles. This system is suited to successive operation in order to fill tubs, cones or pots, with a dwell time during filling, but cannot be used for instance for continuous decoration, since the shapes generated by the movements can be controlled only by the containers receiving the products. Moreover, the mechanism for moving the product distribution tubes is relatively bulky.
European Patent Application No. 485 654 discloses a device distributing alternate layers of chocolate and ice cream into cones or pots which also operates in a successive manner but is of more compact construction than the previous device. This distributor comprises a rotary joint supplying the ice cream vertically in the form of a helical ribbon surrounded by a fixed annular tube from which the chocolate flows and is inserted in the form of strips in the helical ribbon. This device can operate at high speed, while producing a uniform distribution of the layers of chocolate in the ice cream. When it is desired to carry out the continuous extrusion of a decoration using this device, it has to be inclined in order to release the product from the nozzles. Unfortunately, the ice cream then obstructs the chocolate discharge nozzles.